<?php
	/**
	 * jsmin.php - PHP implementation of Douglas Crockford's JSMin.
	 *
	 * This is pretty much a direct port of jsmin.c to PHP with just a few
	 * PHP-specific performance tweaks. Also, whereas jsmin.c reads from stdin and
	 * outputs to stdout, this library accepts a string as input and returns another
	 * string as output.
	 *
	 * PHP 5 or higher is required.
	 *
	 * Permission is hereby granted to use this version of the library under the
	 * same terms as jsmin.c, which has the following license:
	 *
	 * --
	 * Copyright (c) 2002 Douglas Crockford  (www.crockford.com)
	 *
	 * Permission is hereby granted, free of charge, to any person obtaining a copy of
	 * this software and associated documentation files (the "Software"), to deal in
	 * the Software without restriction, including without limitation the rights to
	 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
	 * of the Software, and to permit persons to whom the Software is furnished to do
	 * so, subject to the following conditions:
	 *
	 * The above copyright notice and this permission notice shall be included in all
	 * copies or substantial portions of the Software.
	 *
	 * The Software shall be used for Good, not Evil.
	 *
	 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	 * SOFTWARE.
	 * --
	 *
	 * @package JSMin
	 * @author Ryan Grove <ryan@wonko.com>
	 * @copyright 2002 Douglas Crockford <douglas@crockford.com> (jsmin.c)
	 * @copyright 2008 Ryan Grove <ryan@wonko.com> (PHP port)
	 * @license http://opensource.org/licenses/mit-license.php MIT License
	 * @version 1.1.1 (2008-03-02)
	 * @link http://code.google.com/p/jsmin-php/
	 */

	class JSMin {
		const ORD_LF    = 10;
		const ORD_SPACE = 32;
		
		protected $a           = '';
		protected $b           = '';
		protected $input       = '';
		protected $inputIndex  = 0;
		protected $inputLength = 0;
		protected $lookAhead   = null;
		protected $output      = '';
		
		// -- Public Static Methods --------------------------------------------------
		public static function minify($js) {
			$jsmin = new JSMin($js);
			return $jsmin->min();
		}
		
		// -- Public Instance Methods ------------------------------------------------
		public function __construct($input) {
			$this->input       = str_replace("\r\n", "\n", $input);
			$this->inputLength = strlen($this->input);
		}
		
		// -- Protected Instance Methods ---------------------------------------------
		protected function action($d) {
			switch($d) {
				case 1:
					$this->output .= $this->a;
				case 2:
					$this->a = $this->b;
					if ($this->a === "'" || $this->a === '"') {
						for (;;) {
							$this->output .= $this->a;
							$this->a       = $this->get();
							if ($this->a === $this->b) {
								break;
							}
							if (ord($this->a) <= self::ORD_LF) {
								throw new JSMinException('Unterminated string literal.');
							}
							if ($this->a === '\\') {
								$this->output .= $this->a;
								$this->a       = $this->get();
							}
						}
					}
				case 3:
					$this->b = $this->next();
					if ($this->b === '/' && (
						$this->a === '(' || $this->a === ',' || $this->a === '=' ||
						$this->a === ':' || $this->a === '[' || $this->a === '!' ||
						$this->a === '&' || $this->a === '|' || $this->a === '?')) {
							$this->output .= $this->a . $this->b;
							for (;;) {
								$this->a = $this->get();
								if ($this->a === '/') {
									break;
								} elseif ($this->a === '\\') {
									$this->output .= $this->a;
									$this->a       = $this->get();
								} elseif (ord($this->a) <= self::ORD_LF) {
									throw new JSMinException('Unterminated regular expression '.'literal.');
								}
								$this->output .= $this->a;
							}
							$this->b = $this->next();
						}
			}
		}
		
		protected function get() {
			$c = $this->lookAhead;
			$this->lookAhead = null;
			if ($c === null) {
				if ($this->inputIndex < $this->inputLength) {
					$c = $this->input[$this->inputIndex];
					$this->inputIndex += 1;
				} else {
					$c = null;
				}
			}
			if ($c === "\r") {
				return "\n";
			}
			if ($c === null || $c === "\n" || ord($c) >= self::ORD_SPACE) {
				return $c;
			}
			return ' ';
		}
		
		protected function isAlphaNum($c) {
			return ord($c) > 126 || $c === '\\' || preg_match('/^[\w\$]$/', $c) === 1;
		}
		
		protected function min() {
			$this->a = "\n";
			$this->action(3);
			while ($this->a !== null) {
				switch ($this->a) {
					case ' ':
						if ($this->isAlphaNum($this->b)) {
							$this->action(1);
						} else {
							$this->action(2);
						}
						break;
					case "\n":
						switch ($this->b) {
							case '{': case '[': case '(': case '+': case '-':
								$this->action(1);
								break;
							case ' ':
								$this->action(3);
								break;
							default:
								if ($this->isAlphaNum($this->b)) {
									$this->action(1);
								} else {
									$this->action(2);
								}
						}
						break;
					default:
						switch ($this->b) {
							case ' ':
								if ($this->isAlphaNum($this->a)) {
									$this->action(1);
									break;
								}
								$this->action(3);
								break;
							case "\n":
								switch ($this->a) {
									case '}': case ']': case ')': case '+': case '-': case '"': case "'":
										$this->action(1);
										break;
									default:
										if ($this->isAlphaNum($this->a)) {
											$this->action(1);
										} else {
											$this->action(3);
										}
								}
								break;
							default:
								$this->action(1);
								break;
						}
				}
			}
			return $this->output;
		}
		
		protected function next() {
			$c = $this->get();
			if ($c === '/') {
				switch($this->peek()) {
					case '/':
						for (;;) {
							$c = $this->get();
							if (ord($c) <= self::ORD_LF) {
								return $c;
							}
						}
					case '*':
						$this->get();
						for (;;) {
							switch($this->get()) {
								case '*':
									if ($this->peek() === '/') {
										$this->get();
										return ' ';
									}
									break;
								case null:
									throw new JSMinException('Unterminated comment.');
							}
						}
					default:
						return $c;
				}
			}
			return $c;
		}
		
		protected function peek() {
			$this->lookAhead = $this->get();
			return $this->lookAhead;
		}
	}

	// -- Exceptions ---------------------------------------------------------------
	class JSMinException extends Exception {}
?>